Nov., 1912 THE JOL-RSA4L OF ILVDCSTRIrlL AND ENGINEERING

degree of resistance that could be attained with con- siderable quantities of copper present. Kos. 3 and 6 were substantially of the same resistivity ...
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Nov.,

1912

T H E J O L - R S A 4 L OF I L V D C S T R I r l L A N D E N G I N E E R I N G C H E M I S T R Y .

degree of resistance that could be attained with considerable quantities of copper present. Kos. 3 and 6 were substantially of the same resistivity but ?So. 3 was more sluggish in pouring. Very little difference could be detected between Kos. 5 and 6 , hence the latter was taken a.s a basis for further experiments. I t n-as evident from the impossibility of securing perfect cast material from No. 6 t h a t a study must be made of purging agents to clear the bath of oxides and dissolved gases. Aluminum could be used to advantage in this regard while a t the same time the resistance t o the acids was slightly increased. Tungsten was a slight further aid and manganese up to a n amount equaling I per cent. did not appreciably augment the solubility factor. Other deoxidizers and denitrifiers in various forms were used, such as boron, silicon, titanium and vanadium--the effect of the last one, seemingly, t o increase the solubility. The others in fractional percentages were effective both in improving the resistivity and the texture as well. The average range of values employed was approximately as follows: TABLE III.-SHOWINGCOhIPOSITION O F ACID RESISTASTALLOY. Xi . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66.6 . . . . . . . . . . . . . . . . . . 18.0 .................. 8 5 ......................................... 3.3 . . . . . . . . . . . . . . . . . . 2.0 n. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.0 Ti. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.2 B ................................. 0.2 Si . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.2

__

100.0

Not all of the difficulties of casting the material have been eliminated b y any means. I n proportion as the texture and soundness have been improved upon, the difficulties connected with casting the material have increased. The contraction of the metal a t the moment of solidification is very pronounced and shrinkage cracks are very likely to occur. However, these difficulties are chiefly physical and mechanical and in each specific condition they can doubtless be finally overcome. The alloy draws into wire and spins readily and may have numerous interesting applications. As a method for more precisely measuring the acid resistance of the material, test pieces were prepared having a n easily determined superficial area. These pieces were subjected t o 4 N HNO, and in mixtures of nitric and sulphuric acids of similar concentration, for 24 hours a t room temperature. The loss in weight was calculated t o a unit area of I O O sq. cm. per hour. The comparative values are given in Table IV. The various melts differed slightly in composition, the attempt being made t o determine the limits of certain ingredients, especially manganese, copper and aluminum. The best results were obtained with compositions conforming most nearly to the values given in Table 111. The solubility in sulphuric acid was found t o be as a rule no greater than in nitric acid, hence, the solubility tests were made on mixtures of the two instead of upon the sulphuric acid alone. Very few tests on hydrochloric acid were made. As a rule the solubility of this type of alloy is considerably

TABLEIV.-SHOWING Loss

IS

MILLIGRAMS PER 100 SQ. CM.

4NHNOs. NUMBER OF 23

3iELT.

...

mg.

0.03 0.03 0.50 0.06

4NH2S04 mg.

845 PER

HOUR.

1 v01. 4NHNOs. 4NHC1. 2 vol. 4NH2SOI.

0.79

mg.

mg.

1.95

1.95 1.98

25 . . . . . . . . . . . . . . . . . 0.19 0.08

0.0 0.17 1.10 1.30

0.09

3.70

0.8

60. . . . . . . . . . . . . . . . . 0.2 0.4

1.95 2 .05

4.8 5.2

64 . . . . . . . . . . . . . . . . .

2.70

0.3

0.10 1 .oo

2.0 1.85

0.3 0.2

greater in hydrochloric acid than in nitric or sulphuric acids.1 Indeed, a study of the various properties of the material up to the present time has been preliminary and largely qualitative. The detailed examination on structure, solubilities, physical and electrolytic properties has been deferred until a practicable or workable alloy could be obtained. This has now been accomplished in a very satisfactory manner and further work as above indicated will be continued. As illustrating the practical value of the alloy a calorimeter bomb was constructed and has already served for heat determinations upon a n extended series consisting of sugar, benzoic acid, ethyl-benzene and coals. The pressures employed have ranged from 2j-50 atmospheres and charges of material up to The results are all that IT/* grams have been used. could be desired. An illustration of the cap or cover t o the bomb was given in my article published in THIS JOURSAL, page 746. The interior surface which comes in coqtact with the corroding gases retains its polish and luster without any evidence of chemical action. The details of the behavior of the alloy in this apparatus were given in a paper entitled "Some Tests on a New Calorimeter Bomb," by Dr. R. H. Jesse, Jr., THIS J O U R N A Lpage , 748. UNIVERSITY O F ILLINOIS, URB.AXA.

MODIFIED BUNSEN VALVE. B y LESLIERUSSELLMILFORD.

Received August 12, 1912.

I n making analyses of total iron, the following scheme has been adopted by the author in working on the Saratoga Mineral Waters. When reducing the ferric compounds to ferrous, by means of nascent hydrogen, a n Erlenmeyer flask with a Bunsen valve attachment has been used. The accompanying cut shows a t a glance the modification which has been satisfactory. A, Erlenmeyer flask. B, Cork. C, Bulb cut from I O cc. pipette. D, Rubber tubing. E,Glass plug. SS', Slits for valve. "Stellite," a cobalt-chrome alloy described by E . Haynes. THIS 2, 397 (1910), shows a solubility under the same conditions of li milligrams per 100 s q . cm. 1

JOURNAL

Instead of an ordinary straight piece of glass tubing a bulb, C, from a discarded I O cc. pipette is used, one end ' of which is inserted into the cork B, projecting just below the surface into the Erlenmeyer flask A; t o the other end is joined a piece of ruhbertubing, D, carrying a glass plug, E. The ferric solution to be reduced is put into the Erlenmeyer flask, dilute suiphuric acid and zinc dust are added and the flask is then placed on the steam bath. The nascent hydrogen produced by the action of the acid on thf zinc reduces t h e iron rapidly. When all ai the zinc is in solution the flask is taken from the bath, placed on a wire gauze and the contents are brought to boiling so as to eliminate any hydrogen in the flask as this would decompose the KMnO, solution when added. I t is a t this point that the improvcd valve works t o advantage. The

steam in escaping expands in the I O cc. bulb, condenses and runs back into t h e flask. This eliminates the excess pressure and blowing out of the stopper. After thorough boiling, the flask is taken from the gauze, the stopper removed, the sides washed down, and a very little c. P. XaHCO, is

I

dropped into the flask to generate an atmosphere of CO,. The solution is then titrated with standard KMnO,. STAT%H ~ c i e v i cL A ~ O ~ A T O R Y , ALB*NY. 3.

1

Morris Loeh, President of the Chemists' Club of New York City, died at Seabright, New Jersey, October 8, 3 9 1 2 , from l'resented at the October meeting of the American Chemicnl Society. 1

m w york

Section

the

-

A SIMPLE FORM OF LABORATORY SUPPORT. B,.

r.L S N S cnossLcy. ~ ~

Reccived .41igurf 21, 1912.

The accompanying illustration shows a form of support for apparatus which has been found very useful in this laboratory. It consists of inch rod and pipe fittings. The footing pieces are screwed into round plates and fastened to t h e bench. The size of rod is such as to suit the usual retort stand fittings. It has the advantages of lightness, firmness, adaptability, and cheapness. I t does away with the heavy undergrowth of retort stand footing. Any pipe fitter can make such apparatus very quickly. Other forms and uses will readily suggest themselves. The apparatus shown is carrying three

vertical condensers and apparatus for Kjeldahl distillations, a Liebig condenser and a Jones reductor, with space for other work, taking the place of five retort stands and several tripods with their accompanying risk of breakage. MONTBEA,,,

OBITUARIES "rnnnrr r n m n -ur.mzo IIULD:

Y.

a,,saac.

1

typhoid fever and double pneumonia, after an illness of eighteen .. days. He was born in Cincinnati, Ohio, Hay 23, 1863. l ~ , , ~I,&,~ i ~ a in speakine of I -ish I might have had timc i o choose m; \s.ordS with more deliberat&. His nature showed itself always in such a refinement as to command its tracing only with the most delicate touch. Tender